1. Field of the Invention
This invention relates to a photo-curing polysiloxane composition, more particularly to a photo-curing polysiloxane composition for forming a planarizing film for a substrate of a liquid crystal display (LCD), an organic electroluminescene display, and the like, an interlayer insulating film, and a core or a cladding of an optical waveguide as a protective film. This invention also relates to a protective film formed from the photo-curing polysiloxane composition and an element containing the protective film.
2. Description of the Related Art
Recently, in order to obtain high resolution and high definition of an image quality for a display, such as a liquid crystal display, an organic electroluminescene display, or the like, a method for improving an aperture ratio of a display is used in the art. JP 9-152625 discloses a method for improving the aperture ratio by providing a transparent and planarizing protective film on a TFT substrate so as to overlap a data line and a pixel electrode.
The protective film is generally formed from a material having good heat resistance and high transparency. JP 10-153854 and JP 2001-281853 disclose a photosensitive resin composition, which includes alkali-soluble acrylic resin, a compound containing a quinonediazido group, a crosslinker or a photo-acid generator. However, these photosensitive resin compositions are insufficient in heat resistance, and the protective film formed from the photosensitive resin composition may have problems, such as discoloration and transparency reduction if treated at a high temperature.
On the other hand, JP 2004-10696 discloses a resin composition which is resistant to oxidative decomposition. The resin composition includes a resin having an imide structure, a siloxane polymer, a photo-acid generator, and a crosslinker. Although a protective film having high transparency can be formed from the resin composition, the protective film is insufficient in developing property and film thickness uniformity during development process.
It is still required in the art to provide a photosensitive resin composition which can be used to form a protective film having superior properties, such as transparency, developing property, and film thickness uniformity.